Contents - Faperta

456 Biotechnological Approaches for Pest Management and Ecological Sustainability
their metabolic products, for example, mycotoxins. This may result in a trade-off between
“nature’s pesticides” produced by transgenic plants and varieties from traditional breeding
programs, synthetic pesticides, mycotoxins, or other poisonous products of insect
pests. Allergenicity assessment must consider several factors, including the source of the
transferred protein, expression levels, the physical and chemical properties of the protein,
and similarity to known allergens. Although no single factor can be considered defi nitive,
consideration of all these factors together may provide some indication of potential allergenicity
(Gendel, 1998).
All Bt proteins have been subjected to allergenicity tests. With the exception of Cry9C,
all are degraded quickly in the stomach, and are unstable when heated. The Cry9C is stable
under simulated stomach conditions, but it is not glycosylated and has not caused any
adverse effects or shown characteristics of immune system responses in mammalian toxicity
studies (Carpenter et al., 2002). It has been suggested that ingredients in vegetative cells
and parasporal bodies of Bt may trigger immune reactions rather than crystalline proteins
expressed in plants (Bernstein et al., 1999).
Bollgard cotton lacks the characteristics found in potential allergenic proteins (Perlak
et al., 2001). Genetically modifi ed maize with an amaranth globulin protein termed amarantin
showed 4% to 35% more protein and 0% to 44% higher amounts of specifi c essential
amino acids as compared to nontransgenic maize (Sinagawa Garcia et al., 2004). Individual
sequence analysis with known amino acid sequences reported as allergens showed that
none of these IgE elicitors were identifi ed in amarantin. Amarantin was digested in
15 minutes by simulated gastric fl uid as observed by Western blot. Expressed amarantin
did not induce levels of specifi c IgE antibodies in BALB/c mice, as analyzed by ELISA, and
therefore, transgenic maize with amarantin is not an important allergenicity inducer, just
as nontransgenic maize.
Public Attitude to Food from Transgenic Plants
Public perception is likely to have a great impact on innovation, introduction, and diffusion
of products of biotechnology. And negative public perception is likely to keep the
products of biotechnology away from the marketplace. Public perception is infl uenced by
a broad range of issues, including environmental safety, ethics, legal repercussions, economic
gain, and socioeconomic impact. Public opinion can be infl uenced by nonscientifi c
considerations based on impressions created by the media and pressure groups. Concerns
about recombinant technology were raised in the early 1970s, and even led to protests over
setting up of biotechnology laboratories in developed countries (Leopold, 1993). As a
result, regulations and guidelines for handling DNA-based technologies were formulated.
With increasing stakes for economic gains and potential risks, public debate over the need
to develop regulatory mechanisms became all the more important. This also led to intense
public debate among scientists, particularly between molecular geneticists and ecologists.
As a result, the politicians, the industry, and environmental groups began to take a more
active stance. Much of this debate is likely to play itself out in the regulatory arena, with
the shift of focus from the laboratory to commercial applications. This role needs to be
taken up by international and national research organizations for agriculture, health, food,
and the environment.